Enthalpy of formation is calculated by subtracting the total enthalpy of formation of the reactants from those of the products. This is called the HESS' LAW.
ΔHrxn = ΔH(products) - ΔH(reactants)
Since the enthalpies are not listed in this item, from reliable sources, the obtained enthalpies of formation are written below.
ΔH(C2H5OH) = -276 kJ/mol
ΔH(O2) = 0 (because O2 is a pure substance)
ΔH(CO2) = -393.5 kJ/mol
ΔH(H2O) = -285.5 kJ/mol
Using the equation above,
ΔHrxn = (2)(-393.5 kJ/mol) + (3)(-285.5 kJ/mol) - (-276 kJ/mol)
ΔHrxn = -1367.5 kJ/mol
<em>Answer: -1367.5 kJ/mol</em>
8,002.5 would be written as
8.0025 x 10 and 3
because you move the decimal place 3 times to the left.
Answer:
each of the above (A, B, and C) occurs
Explanation:
When an ionic compound dissolves in the water, the following happens :
-- the solvent solute attractive forces tries to overcome the solute solute attractions.
-- the water dipoles' negative end attracts the positive ions
-- the water dipoles' positive end attracts the negative ions
For example,
NaCl which is an ionic compound and also a strong electrolyte, it dissociates into water on the hydrated Na cations as well as Cl anions.
In water, the oxygen has negative charge and thus attracts the positive ions of the sodium, whereas the hydrogen is of positive and it attract the ions of chlorine which is negative.
